1. Technical Field
The disclosure relates to an imaging device provided at a distal end of an insertion portion of an endoscope, the endoscope being configured to be inserted into a subject to image an inside of the subject, and relates to an endoscope device.
2. Related Art
Conventionally, endoscope devices have been widely used for various examinations in a medical field and an industrial field. Among them, endoscope devices for medical use have been widely used since observation or the like of a subject site can be performed by inserting, into a body cavity of a subject such as a patient, an elongated flexible insertion portion having a distal end portion in which an imaging device has been incorporated, and medical treatment can be performed by causing a treatment tool to project from a distal end of the insertion portion as necessary.
In recent years, due to an enlarged light receiving region and a large image sensor caused by mounting of a processing circuit, an imaging module has been proposed in which an image sensor is arranged substantially in parallel with an optical axis of an objective lens group, and light is reflected by a prism on the image sensor and received by the image sensor (for example, refer to JP 2008-79823 A and JP 2011-237525 A).
As a technique for thinning a diameter of an insertion portion of an endoscope device to reduce a burden on an examinee, an imaging device has been proposed in which a CCD unit (where an optical member is fixed to an image sensor) is fitted, directly by the optical member, into a lens frame where a lens group has been incorporated (for example, refer to JP 2002-131656 A).